Patent GB-433444-A (GB)
Title: Improvements in and relating to washing machines
IPC: A47L15/42
Filed: 1935-04-26
Abstract: 433,444. Dishwashing machines. BRITISH THOMSONHOUSTON CO., Ltd., Crown House, Aldwych, London. April 26, 1935, No. 12562. Convention date, April 26, 1934. [Class 138 (i)] An electrically-operated dish - washer is manually controlled to effect each of a plurality of cleaning steps such as washing and rinsing, and if desired, will automatically effect a complete or a partial timed washing cycle. The invention, while not limited thereto, is described in connection with a spraying and impeller apparatus with the dishes supported in a vat 17, Fig. 1 which shows the apparatus in elevation. The electric control is indicated in Fig. 3 and the hand control in Fig. 2. The apparatus operates as follows. With the control member 70, Fig. 2, in the " Off " position the controlling cams shown in Fig. 3 and right hand corner of Fig. 1 will have opened all the switches to de - energize the apparatus. Thus a water inlet valve 37 Fig. 1 will be spring closed and a drain valve 41 hinged at 43 will be opened by a spring 45, and a detergent valve 54 will be closed. An impeller motor 21 and a programme motor 71 and indicator lamp 74, Fig. 3 will all be de-energized. To effect a " rinse " the control 70 will be manually turned clockwise to first rinse position. This will operate a shaft 78, Fig. 1, on which the cams are mounted so that cam 65, Fig. 3, will bring a projection 90 to close switch 61 thereby operating magnet 37<b> to open water inlet 37. Cams 64, 66, 69 and 73 controlling the motor 21, detergent valve 54, drain 41 and programme motor 71 will remain inactive but the cam 76 will close switch to the lamp 74. Water will flow from source 36 to reaction spray device 28 to rinse the dishes in the racks 16 &c., and will drain away. To effect a wash by the impeller 20, the control 70 is turned to " Wash." The cam 64 will bring a projection 91, Fig. 3 to close a switch 60 to operate the impeller motor 21. The cam 65 will move but will hold the switch 61 to keep open the inlet valve 37. The cam 67 will engage the switch 63 to operate the magnet 46 to close the drain valve 41. The cam 76 will still hold the switch 75 to maintain the lamp 74 alight. The cam 66 has no action on the detergent valve 54 and the cam 73 none on the motor 71. Water will collect in the vat and be engaged by the impeller 20 for washing. When a predetermined quantity of water is supplied to the vat, the inlet valve 37 will be closed by a switch 94, Fig. 3 connected in the circuit of the magnet 37b. The switch is controlled by the magnet 95 which is connected to the armature circuit of the motor 21 and hence is proportional to the load. As the water rises the load increases and the coil will be energized to open the switch 94. The device 37b will be de-energized to close the valve 37 against the spring 37<a> cutting off the water supply. The wash will be continued till the hand control is moved. The control could be moved to the " Wash " position without effecting the rinsing step, and the rinsing step could be had without the washing step. If it be desired to operate the motor to drive a pulley 86, Fig. 1 on a flexible shaft 87 to connect with a driving socket 88, Fig. 2, for driving any external auxiliary appliances without any cleansing action, the hand control will be moved to " motor position. The cam member 64 will cause a projection 96 to close a switch 60 to energize the motor 21. The remaining cams will effect no control. The control 70 can be moved completely through its manual sector without moving the motor 71 on account of a friction clutch 80, Fig. 1 permitting independent motion of the shaft 68. If it be desired to effect an automatic washing operation including rinsing and washing steps the control member 70 will be moved to its position " rinse auto." when the machine will be in automatic control of the programme motor 71. The cams will have moved so that the lift 97 of the cam 64 will close the switch 60 to operate the motor 21. A lift 100 of the cam 73 will close the switch 72 to operate the programme motor 71. Other cams will effect a rinsing action. The motor 71 will advance the shaft 68 to the wash position and washing will take place as before. This action will continue till the " drain " position. The motor 71 will continue to turn the shaft 68 to the second wash, second drain and second rinse. This completes the cycle. The cam lifts are so arranged that each step of the automatic cycle will take a certain time interval. In a specific example-the total time will be fifteen minutes. First rinse one and a half minutes. First wash five minutes. First drain half a minute. It is not necessary to go through the complete automatic cycle. If the control be moved directly to any posi. tion in the automatic range the motor 71 will pick up from that position.